Current radar systems operating at the microwave range include an antenna. The antenna includes an array of resonating elements mounted onto a substrate. The antenna array includes a plurality of resonating lines. Each resonating line includes a plurality of axially aligned resonators. Power is supplied to each resonating line through a feed line.
In certain embodiments, the feed line is proximately coupled to each of the resonating lines. The feed lines are mounted on the substrate and are generally disposed beneath the resonating lines. Electricity is supplied along the feed lines, actuating the resonators so as to receive echoes from a transmitting antenna. However, a concentration of electrical field forms along the mid portion of the antenna array, as shown in FIG. 1. This concentration affects the radiation efficiency of the antenna, and may generate a side lobe (as shown in FIG. 4) which may affect the accuracy of the antenna.
Accordingly, it remains desirable to have an antenna having an array proximately coupled to the feed line which reduces the concentration of electrical field along the mid portion of the antenna array.